man virt-inspector virt-inspector [--options] -d domname virt-inspector [--options] -a disk.img [-a disk.img ...] virt-inspector --help virt-inspector [--options] -d domname file [file ...] virt-inspector [--options] -a disk.img [-a disk.img ...] file [file ...] virt-inspector -V virt-inspector 1.36.3rhel=7,release=6.el7_4.3,libvirt
Patch posted: https://www.redhat.com/archives/libguestfs/2018-February/msg00080.html
Fixed with https://github.com/libguestfs/libguestfs/commit/62b09ba0b0942d36b4e238b242513157babccb44 which libguestfs >= 1.39.1.